[test] Disable crashing web-snapshot test

Failure link:
https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/37294/overview

Started crashing after CL:
https://chromium-review.googlesource.com/c/v8/v8/+/2929382

Bug: v8:11842
No-Try: true
Change-Id: I68613a9cede8f2f90a46725e34cde87cb6e46d81
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2931806Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Auto-Submit: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74907}

test/mjsunit/mjsunit.status

@@ -197,6 +197,9 @@
   'regress/regress-crbug-941743': [PASS, HEAVY],
   'regress/regress-crbug-1191886': [PASS, HEAVY],
   'wasm/externref-globals': [PASS, HEAVY],
+
+  # TODO(cbruni): Reenable once custom snapshot is fixed.
+  'web-snapshot/web-snapshot': [SKIP],
 }],  # ALWAYS
 
 ##############################################################################